1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2010 ASIX Electronics Corporation
4 * Copyright (c) 2020 Samsung Electronics Co., Ltd.
5 *
6 * ASIX AX88796C SPI Fast Ethernet Linux driver
7 */
8
9 #define pr_fmt(fmt) "ax88796c: " fmt
10
11 #include <linux/string.h>
12 #include <linux/spi/spi.h>
13
14 #include "ax88796c_spi.h"
15
16 const u8 ax88796c_rx_cmd_buf[5] = {AX_SPICMD_READ_RXQ, 0xFF, 0xFF, 0xFF, 0xFF};
17 const u8 ax88796c_tx_cmd_buf[4] = {AX_SPICMD_WRITE_TXQ, 0xFF, 0xFF, 0xFF};
18
19 /* driver bus management functions */
axspi_wakeup(struct axspi_data * ax_spi)20 int axspi_wakeup(struct axspi_data *ax_spi)
21 {
22 int ret;
23
24 ax_spi->cmd_buf[0] = AX_SPICMD_EXIT_PWD; /* OP */
25 ret = spi_write(ax_spi->spi, ax_spi->cmd_buf, 1);
26 if (ret)
27 dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
28 return ret;
29 }
30
axspi_read_status(struct axspi_data * ax_spi,struct spi_status * status)31 int axspi_read_status(struct axspi_data *ax_spi, struct spi_status *status)
32 {
33 int ret;
34
35 /* OP */
36 ax_spi->cmd_buf[0] = AX_SPICMD_READ_STATUS;
37 ret = spi_write_then_read(ax_spi->spi, ax_spi->cmd_buf, 1, (u8 *)status, 3);
38 if (ret)
39 dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
40 else
41 le16_to_cpus(&status->isr);
42
43 return ret;
44 }
45
axspi_read_rxq(struct axspi_data * ax_spi,void * data,int len)46 int axspi_read_rxq(struct axspi_data *ax_spi, void *data, int len)
47 {
48 struct spi_transfer *xfer = ax_spi->spi_rx_xfer;
49 int ret;
50
51 memcpy(ax_spi->cmd_buf, ax88796c_rx_cmd_buf, 5);
52
53 xfer->tx_buf = ax_spi->cmd_buf;
54 xfer->rx_buf = NULL;
55 xfer->len = ax_spi->comp ? 2 : 5;
56 xfer->bits_per_word = 8;
57 spi_message_add_tail(xfer, &ax_spi->rx_msg);
58
59 xfer++;
60 xfer->rx_buf = data;
61 xfer->tx_buf = NULL;
62 xfer->len = len;
63 xfer->bits_per_word = 8;
64 spi_message_add_tail(xfer, &ax_spi->rx_msg);
65 ret = spi_sync(ax_spi->spi, &ax_spi->rx_msg);
66 if (ret)
67 dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
68
69 return ret;
70 }
71
axspi_write_txq(const struct axspi_data * ax_spi,void * data,int len)72 int axspi_write_txq(const struct axspi_data *ax_spi, void *data, int len)
73 {
74 return spi_write(ax_spi->spi, data, len);
75 }
76
axspi_read_reg(struct axspi_data * ax_spi,u8 reg)77 u16 axspi_read_reg(struct axspi_data *ax_spi, u8 reg)
78 {
79 int ret;
80 int len = ax_spi->comp ? 3 : 4;
81
82 ax_spi->cmd_buf[0] = 0x03; /* OP code read register */
83 ax_spi->cmd_buf[1] = reg; /* register address */
84 ax_spi->cmd_buf[2] = 0xFF; /* dumy cycle */
85 ax_spi->cmd_buf[3] = 0xFF; /* dumy cycle */
86 ret = spi_write_then_read(ax_spi->spi,
87 ax_spi->cmd_buf, len,
88 ax_spi->rx_buf, 2);
89 if (ret) {
90 dev_err(&ax_spi->spi->dev,
91 "%s() failed: ret = %d\n", __func__, ret);
92 return 0xFFFF;
93 }
94
95 le16_to_cpus((u16 *)ax_spi->rx_buf);
96
97 return *(u16 *)ax_spi->rx_buf;
98 }
99
axspi_write_reg(struct axspi_data * ax_spi,u8 reg,u16 value)100 int axspi_write_reg(struct axspi_data *ax_spi, u8 reg, u16 value)
101 {
102 int ret;
103
104 memset(ax_spi->cmd_buf, 0, sizeof(ax_spi->cmd_buf));
105 ax_spi->cmd_buf[0] = AX_SPICMD_WRITE_REG; /* OP code read register */
106 ax_spi->cmd_buf[1] = reg; /* register address */
107 ax_spi->cmd_buf[2] = value;
108 ax_spi->cmd_buf[3] = value >> 8;
109
110 ret = spi_write(ax_spi->spi, ax_spi->cmd_buf, 4);
111 if (ret)
112 dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
113 return ret;
114 }
115
116